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Star Power: An Analysis of Digital Astrology Content as an Instrument of Political Tractability
Get PDFIn an essay from 1953 titled, The Stars Down to Earth, Theodor Adorno performed an exacting analysis of the weekly horoscopes published in The Los Angeles Times to illuminate the latent authoritarianism embedded in the rhetoric of astrology. One of Adorno’s primary arguments is that an insidious form of political tractability is forged through the simultaneous determinism and individualism of astrology. Seventy years after The Stars Down to Earth, the genre of short-form astrology videos has skyrocketed in popularity across social media platforms. This essay offers a series of close readings of digital astrology videos to theorize both the allure and the ideological implications of astrology’s contemporary resurgence.
To begin, this essay conceptualizes astrology through the Lacanian, psychoanalytic framework of the symbolic order. This discussion of the symbolic order leads into a close reading of the birth chart —specifically the structural absences of the birth chart— to expose the latent fantasies and political consequences embedded in the ways that astrology constitutes subjectivity. These absences are the omission of intersubjectivity, the failure to account for intermediary structures of authority, and the erasure of the family kinship structure. Following this psychoanalytic lens, this project considers theories of digitality and divinity to illustrate how technological advancements have democratized access to the epistemological breadth of astrology and enhanced its mystical power
Conserving the Public Lands: Policy and Spatial Analysis of a Bureau of Land Management Conservation Leasing Mechanism
Get PDFThe Bureau of Land Management (BLM) is the largest land administrator in the United States, managing about 10% of U.S. lands, primarily in the Western states. The BLM manages under a multiple-use framework, issuing commercial authorizations for grazing, mining, oil and gas, and wind and solar on public lands, while also managing for ecosystem health. In April 2024, the agency finalized a rule that would create a conservation leasing mechanism to allow private, state, and tribal parties to lease BLM lands for restoration and mitigation purposes, which I investigate here. First, I find that while the conservation leasing mechanism does not create a direct pathway to negotiate changes to other use authorizations, it could be used to cement prior authorization modifications. Second, I explore opportunities for conservation leasing on BLM lands with GIS analysis. I find that the BLM holds nearly 10% of areas of unprotected biodiversity importance in the conterminous U.S. and that BLM grazing and oil and gas authorizations are located on 85% and 16% of these areas, respectively. I also find that 57 endangered and threatened species have over 10% of critical habitat on BLM land, and 25 listed species have over 10% of critical habitat on BLM land authorized for grazing. Stressors to these species are diverse, including activities authorized on BLM lands and other factors. I also find over 40% of big game habitat in Utah is located on BLM lands and that BLM grazing is authorized on over 90% of these lands. Third, by building models for solar development in the Western U.S. using multi-criteria analysis, I find that critical habitat for endangered species occurs on less than 3% of land most suitable for solar development. Conservation leasing on BLM lands could offset 10-20% of this impact, but adding BLM lands to areas already available for other mitigation opportunities only modestly increases the total area that could be offset through compensatory mitigation. Given the large overlap between high-priority conservation areas and other uses, I conclude by recommending that the BLM strengthen property rights for authorizations across uses to facilitate voluntary negotiations between users. Stronger rights attached to grazing authorizations, for instance, would allow stakeholders to apply local knowledge to realize grazing practices aligned with ranching and conservation priorities. Paired with restoration and mitigation leasing, I suggest that markets for multiple use rights would facilitate mutually beneficial and secure outcomes for oil and gas, grazing, and conservation interests
Consistent Monte Carlo methods for non-linear applications in light transport
Get PDFThe study of light transport focuses on describing the propagation of light from emitters to sensors through accurately describing the interactions light can undergo with everything in between. Physically-based rendering is the process of applying the laws of light transport to formulate practical algorithms which simulate the flow of light for the purpose of synthesizing images of virtual environments.
Unfortunately, there are very few interesting scene configurations which can be computed analytically. Instead, modern solutions predominantly rely on Monte Carlo integration to stochastically estimate the transfer of light since the process is both unbiased and consistent. Meaning, it is expected to give us the correct result, and if we took the average of infinitely many estimates we would obtain the correct answer.
However, the ideal properties of Monte Carlo integration are not guaranteed for all problems. In the presence of non-linear perturbations, Monte Carlo integration will almost always result in incorrect solutions. Unfortunately, applications with non-linear perturbations appear throughout light transport from simulating the interactions between light and participating media, to rendering complicated visual phenomena like caustics, to even modern applications in differentiable rendering.
In this dissertation we focus on formulating consistent solutions for general non-linear problems within light transport. We achieve this by devising a general recipe outlining for both scientists and practitioners alike how to address and account for the many difficulties which can arise when estimating these difficult problems. This involves discussing various ways of reconstructing non-linear problems into alternative forms which are amenable to unbiased Monte Carlo integration. We then review ways of verifying that these unbiased estimators are efficient enough to be employed in practice. When this is not the case, we review and introduce methods for constructing biased, but still consistent, solutions. Through the application of our recipe, we introduce the first general unbiased rendering algorithm capable of rendering non-classical participating media, the first truly unbiased photon-mapping algorithm for rendering razor sharp caustics, and various consistent techniques for efficiently rendering participating media comprised of unknown black box densities
Inflammaging in the Alzheimer’s Brain and Beyond: Insights from a Transgenic Mouse Model on the Sex-specific Pathophysiology of Alzheimer’s Disease
Get PDFAging and sex are major risk factors for developing late-onset Alzheimer’s disease. Compared to men, women experience worse neuropathological burden and cognitive decline despite living longer with the disease. Similarly, male 3xTg-AD mice, developed to model Alzheimer’s disease, no longer consistently exhibit standard Alzheimer’s neuropathology yet experience higher rates of mortality - providing a unique opportunity to further elucidate this dichotomy. We hypothesized that sex differences in the biological aging process yield distinct pathological and molecular Alzheimer’s disease signatures in males and females, which could be harnessed for therapeutic and biomarker development.
We aged male and female, 3xTg-AD and B6129 control mice across their respective lifespans (n=3-8 mice per sex, strain, and age group) and longitudinally assessed neuropathological hallmarks of Alzheimer’s disease, markers of hepatic inflammation, splenic mass and morphology, as well as plasma cytokine levels. We conducted RNA sequencing analysis on bulk brain tissue and examined differentially expressed genes (DEGs) between 3xTg-AD and B6129 samples and across ages in each sex. We also examined DEGs between clinical Alzheimer’s and control parahippocampal gyrus brain tissue samples from the Mount Sinai Brain Bank study in each sex.
3xTg-AD females significantly outlived 3xTg-AD males and exhibited progressive Alzheimer’s neuropathology, while 3xTg-AD males demonstrated progressive hepatic inflammation, splenomegaly, circulating inflammatory proteins, and minimal Alzheimer’s neuropathological hallmarks. Instead, 3xTg-AD males experienced an accelerated upregulation of immune-related gene expression in the brain relative to females. Our clinical investigations revealed that individuals with Alzheimer’s disease develop similar sex-specific alterations in neuronal and immune function. In diseased males of both species, we observed greater upregulation of complement-related gene expression, and lipopolysaccharide was predicted as the top upstream regulator of DEGs.
Our data demonstrate that chronic inflammation and complement activation are associated with increased mortality, indicating that age-related changes in immune response contribute to sex differences in Alzheimer’s disease trajectories. We provide evidence that aging and transgene-driven disease progression trigger a widespread inflammatory response in 3xTg- AD males, which mimics the impact of lipopolysaccharide stimulation despite the absence of infection
On generating bijections for permutations and inversion sequences
Get PDFGiven an algebraic proof of a combinatorial identity, we use recursive methods to construct a bijection demonstrating the identity.
Our first application centers around derangements and nonderangements. A derangement is a permutation with no fixed point, and a nonderangement is a permutation with at least one fixed point. There is a one-term recurrence for the number of derangements of n elements, and we describe a bijective proof of this recurrence which can be found using a recursive map. We then show the combinatorial interpretation of this bijection and how it compares with other known bijections, and show how this extends to an involution. Nonderangements satisfy a similar recurrence. We convert the bijective proof of the one-term identity for derangements into a bijective proof of the one-term identity for nonderangements.
We then consider identities proven via inclusion-exclusion. An inversion sequence is an integer sequence e = e_1 e_2 ... e_n such that 0 ≤ e_i \u3c i for all 1 ≤ i ≤ n. Inversion sequences of length n are in bijection with permutations in S_n. A pattern is a sequence p = p_1 p_2 … p_r with p_i in {0, 1, …, r - 1} for all 1 ≤ i ≤ r such that j can only appear in p if j - 1 also appears, and an inversion sequence e is said to contain the consecutive pattern p if there is a consecutive subsequence of e whose reduction is p; otherwise, e is said to avoid p. We say two patterns p and q are Wilf equivalent if the number of inversion sequences of length n which avoid p is equal to the number of inversion sequences of length n which avoid q. In previous work, Auli and Elizalde characterized generalized Wilf equivalences among all 75 consecutive patterns of length 4, proving some with direct bijections and some via inclusion-exclusion arguments. For those proved by inclusion-exclusion, we derive bijective proofs of these equivalences. We also give new bijective proofs of a stronger relation among some consecutive patterns
Remote Sensing-Based Analysis of Urban Heat Islands and Historical Housing Discrimination In Boston, MA
Get PDFSince 2020, annual average temperatures for Boston, Massachusetts, have ranked within the top 10 hottest years, with 2021 becoming Boston’s hottest year on record (Northeast Regional Climate Center, 2023). Heat is more extreme in urban areas because of the Urban Heat Island (UHI) effect, a temperature difference between urban and suburban areas. This effect is visible between neighborhoods within urban areas, as more densely built regions are often multiple °C hotter than greener areas (Marando et al., 2021). Neighborhoods affected by discriminatory housing policies are often correlated with higher temperatures, which can disproportionately expose certain groups to heat-related hazards. This thesis used Landsat 8 to measure the radiative temperature difference at the land’s surface, and compared neighborhood average temperatures with historical maps of redlining and measurements of race and levels of diversity to identify who is most affected by extreme heat in Boston, MA. We found a range of temperatures between each redlining designation, with neighborhoods classified as ‘undesirable’ ranging around 4-6 °C higher than ‘desirable’ neighborhoods. The race and temperature analysis indicated that higher percentages of Black and Hispanic people generally live in areas with higher mean temperatures, indicating Black and Hispanic people are more exposed to extreme heat. As mitigating and adapting to extreme heat becomes a priority in urban environments, policies must recognize the unequal distribution of extreme heat and ensure that past discriminatory housing policies do not continue to harm residents